1. Field of the Invention
The present invention relates to a light exposure apparatus and a method for controlling the same.
2. Discussion of the Background
One of the general trends in the area of manufacturing display devices is to increase the size of a mother substrate so as to reduce the production cost. As the size of a mask corresponding to the mother substrate is increased, the manufacturing cost of the mask is exponentially increased which in turn raises the entire process cost.
Thus, to reduce the manufacturing cost accompanied with an increase of the size of the mask, processes not involving a mask, for example, by applying an inkjet printing or a reverse offset printing method, have been considered.
However, such methods are applicable to only some of the entire manufacturing processes of the panel, and basically, photolithography processes using masks are necessary to finish wirings.
Accordingly, exposure methods using a scanning scheme which involves relative movements between a mask and a substrate using a smaller mask for lowering the manufacturing cost have been applied.
A photolithography technique is commonly performed to form pixels and wiring patterns on a display device (a liquid crystal display or a plasma display device). The exposure process during photolithography uses a mask and illuminates an exposure beam through openings provided in the mask.
The exposure beam used in the exposure process may use a light source of various wavelengths such as a laser. A light exposure apparatus, once it is turned on, may continuously emit the exposure beam for a long period of time. However, the intensity of the exposure beam provided by the light exposure apparatus may deteriorate due to the usage of the light exposure apparatus for an extended period of time. Particularly, if used longer than about 120 hours, the light intensity from the light exposure apparatus may be reduced by about 15% such that the intensity of the exposure beam is rapidly reduced and the photolithography process deteriorates.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.